從'const b2Shape *'到'b2PolygonShape *'的動態投射轉換了限定符？

Question

我只是想創建從一個b2Shapeb2PolygonShape，但我有一個錯誤，指出：Dynamic-cast from 'const b2Shape*' to 'b2PolygonShape*' casts away qualifiers

這是我的代碼：

const b2Shape *s = fix2.shape; 
b2PolygonShape *p = dynamic_cast<b2PolygonShape*>(s); 

我在做什麼錯？

Answer 1

這是編譯器抱怨的const限定符。解決方法是將 聲明爲p作爲指向const b2PolygonShape的指針：

const b2PolygonShape *p = dynamic_cast<const b2PolygonShape*>(s);